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from https://openappstack.net/2020/05/14/progress-report-april.html:

Join the newsletter

If you want to stay up to date more than with these monthly updates, join our newsletter. Apart from these updates, we plan to send invitations for test rounds, information about new releases and user research surveys to our newsletter subscribers.

So if you’re interested in using OpenAppStack any time in the future, please sign up here!

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information